Tunneling machine having a rotary cutting ring



Nov. 17, 1959 w. J. KEHALY v2,913,236

'TUNNELING MACHINE HAVING A ROTARY CUTTING RING Filed Aug. 25, 1954 '7 Sheets-Sheet 1 L7 #ETZIZLIT" William a [@MQ) %M\ 221. 5

Nov. 17, 1959 w. J. KEHALY 2,913,236

4 TUNNELING MACHINE HAVING A ROTARY CUTTING RING Filed Aug. 25, 1954 7 Sheets-Sheet 2 WU [1am (I Kefzalg Z: [IL- s Nov. 17, 1959 v w. J. KEHALY 2,913,236

TUNNELING MACHINE x-uwmc A ROTARY cu'r'rmc' RING Filed Aug. 25, 1954 7 Sheets-Sheet 3 Q [I II II II J ll ll II II II HM II M O o o 9 a 9 n o OOQOQOOO Q0 0 0 CO 77 AZ 15 v 5 41 a 1; -1 /=75 9 39 5a oocoo oo s/gmooooooo 75 Zj a A (ll ll$; II ll |l4| 41 l| II II II II I I l A E1225 [ET William I]. Kefzaly Nov. 17, 1959 w. J. KEHALY 2,913,236

TUNNELING' MACHINE HAVING A ROTARY CUTTING RING Filed Aug. 25, 1954 7 Sheets- Sheet 4 54 57 M m I II II II II II I. II I. ll ll I I 47 STJ Paul ET William tl fiehaly Nov. 17, 1959 w. J. KHALY TUNNELING MACHINE HAVING A ROTARY CUTTING RING Filed Aug. 25, 1954 7 Sheets-Sheet 5 Eire: 27.22:?

Wil Iiam c]. Kehaly b w 4 42 UH;

NOV. 17, 1959 w, KE 2,913,236

TUNNELING MACHINE HAVING A ROTARY CUTTING RING FiledAug. 25, 1954 7'Sheets-Sheet 6 fizz-a 2 .1fm?" William (I [fiehaly Nov. 17, 1959 w. J. KEHALY 2,913,235

' mums momma mvmc A aouav cu'r'rmc RING Filed Au 25, 1954 Sheets-Sheet? William J. Kefzaly United States Patent 9 F TUNNELING MACHINE HAVING A ROTARY CUTTING RING William J. Kehaly, Silver City, via Murphy, Idaho Application August 25, 1954, Serial No. 452,143 at Claims. (c1. Zea-'7 The present invention relates to a tunneling machine, and more particularly the present invention relates to a machine to bore a tunnel through earth and rock and the like.

Still more particularly, the present invention relates to a machine operable to bore a tunnel through such materials as bed rock and the like in which instance the machine is operable to bore a clean wall substantially circularly cross-sectioned tunnel which then will not require internal props and bases and the like but which will be usable directly as bored by the machine.

It is, therefore, one of the principal and most important features of the present invention to provide a machine which is operable to bore a clean walled substantially circularly cross-sectioned tunnel through earth or rock or even bed rock and the like whereby such a tunnel may be used as bored as a pedestrian passage or a rolling stock passage or other vehicle passage or as an air tunnel or as a sewer or for any of the other numerous uses to which a tunnel may be put.

Still another important feature and object of the present invention is to provide a new and improved tunneling machine having a cutting assembly which is rotatably disposed at the front of the machine to' rotate peripherally about the front of the machine to out rather than chip or shatter or otherwise disturb the rock formation through which the tunnel is to pass. That is, machines embodying the principles of the present invention have a cutting assembly preferably in the form of a ring which is rotated about its axis and provided withcutting elements such as diamond or other abrasive teeth which will cut a clean ready to use circularly cross-section tunnel as a continuous operation.

Machines embodying the principles of the present invention are provided with a driving and control unit to which there is securely cantilever mounted a debris canister which carries the cutting ring at the front endthereof and peripherally thereabout. The new and'improved driving and control unit has anew and improved frame which is mounted on wheeled trucks for rolling and driving forwardly through the already formed regions of the tunnel.

The wheels on these trucks also preferably have an inner rim which is of larger diameter than the outer rim so that the wheels roll on tracks and rails immediately adjacent to the circular tunnelwall. The tracks themselves preferably lie in inter-facial engagement with the circular tunnel wall and are trapezoidal in cross-sectional configuration whereby the parallelsides o'fthe rails may be disposed vertically so that the-rails will better support the tunneling machine.

The driving unit and control unit, in addition to carrying the driving mechanism such as motor means coupled to the trucks which are drivingly inter-connected, and in addition to carrying all of the operator controlled panel boards and units and the like, further is operative to .carry coolant tanks such aswater tanks and air tanks for coolant to be supplied *to the cutting edgesof the cutter.

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unit and to support the cutting ring and cutting assembly at the forward end of the canister.

The debris canister has a new and improved construction whereby a pair of substantially co-extensive and coaxial drums are held in a radially spaced relation by a 0 plurality of improved double shouldered pins or studs which are secured in appropriate apertures in the drums to extend 'therebetween and space the drums. Longitudinal ducts or substantially confined passages are provided between the drums for the passage of electrical conductors and conduits therefor, water conduits and air conduits all of which lead to the cutting assembly including the cutting ring and a new and improved electric motor drive means therefor and forming a part thereof.

This new and improved electric motor is preferably of the induction-motor type and includes a plurality of wound pole pieces forming a stator and secured to the inner side of the outer canister drum at the leading edge thereof. The rotor for this new and improved motor includes a good conductor ring in which there is recessed and secured a different plurality of magnetic bar elements and which ring is secured to the cutting ring carrying the cutting teeth.

Thus it will be observed that the cutting ring may be so disposed at the front end of the canister that it will float magnetically and be driven to rotate about its axis which is substantially the same as the axis of the debris canister. The cutting ring itself may be mounted on the front end of the canister by having short threads which thread past short threads on the drums so that the ring will not be in any way fixedly secured to the drum or retarded'in its rotation by its mounting on the drum. In addition, roller bearings and the like between the cutting ring and the drums will insure good rolling operation and rotation of the cutting ring.

The cutting ring carries a set of cutting teeth which may be blocks dovetailed onto the front face of the ring, each of the blocks having an abrasive front face formed by such means as diamonds imbedded therein, or other abrasive particles imbedded therein as an example.v v

It is therefore, an important object; of the presentin- .vention to provide a new and improved tunneling machine having a driving and control unitwhich cantilever supportsa canister forwardly thereof and which canister in turn supports a rotary cutting ring at the forward end thereof. It is also an important object and feature of the present invention to provide a new and improved debris canister of a double coaxial drum. construction mounted on a driving and control unit by new and improved bracket and structural assemblies.

Still another object and feature of thepresent invention is to provide a new and improved drive and control unit vto drive and support the remainder of the tunneling machine and to carry segmentally circular or segmental cylindrical coolant tanks and fluid cans andthe like.

Yet another important object of the present invention is the provision of a new and improved rotary cutterfo'r V 3 tion is the provision of a new and improved cutter assembly wherein a rotatable cutting ring is equipped with cutting teeth units having cooperating dovetailed connection with the front face of the cutting ring and further having an abrasive front face such as a diamond particulate front face or other abrasive particulate front face for cutting.

Still another object of the present invention is to provide a new and improved electric motor having new and improved stator pole pieces and windings and a new and improved rotor induction ring element.

Yet another object of the present invention is the provision of a new and improved air coolant system for the cutting assembly and a new and improved water coolant system for the cutting assembly.

Yet another and important object of the present invention is to provide a new and improved tunneling machine wherein the cutter of the tunneling machine cuts a shell cylindrical bore in, earth or rock or the like and leaves a cylindrical core which may then be utilized as large pieces or reduced or shattered or crushed and removed as desired.

Still other objects, features and advantages of the present invention and variations thereof will become readily apparent from the following detailed description of the present invention and an embodiment thereof, from the claims, and from the accompanying drawings in which each and every detail shown is fully and completely disclosed as a part of this specification, in which like reference numerals refer to like parts, and in which:

Figure 1 is a segmental elevational view of the central and forward end portions of a tunneling machine embodying the principles of this invention;

Figure 2 is a side elevational view of the central and rearward portions of the tunneling machine of Figure 1;

Figure 3 is an isometric view of a form of coolant tank or can;

Figure 4 is a segmental sectional View of the driving control unit frame and canister mounting bracket and structural assembly viewed as taken substantially along the line IVIV of Figure 2;

Figure 5 is a segmental sectional view of the same portion of the tunneling machine as shown in Figure 4 but viewed as taken substantially along the line VV of Figure 4;

Figure 6 is a sectional view through the. drive and control unit viewed as taken substantially along the line VI-VI of Figure 2;

Figure 7 is a segmental plan and sectional view of the rolling trucks viewed as taken substantially along the line VII-VII of Figure 6;

Figure 8 is a segmental elevational view of track rails and anchoring units therefor shown partly exploded to better illustrate certain parts thereof;

Figure 9 is a sectional view of a rail viewed as taken substantially along the line IXIX of Figure 8;

Figure 10 is a segmental front end elevational view of the cutting ring and assembly;

Figure 11 is a sectional view of the cutting ring and assembly and of the front end of the canister'and viewed as taken substantially along the line XIXI of Figure 10;

Figure 12 is a segmental sectional view of the motor for rotating the cutting ring and forming a part of the cutting assembly and viewed as taken substantially along the line XIIXII of Figure 11;

Figure 13 is a schematic illustration of the several windings of the stator pole pieces of the motor;

Figure 14 is a schematic illustration of the several parts of the motor shown in their physical placement and relation to each other;

Figure 15 is a schematic illustration of a form of motor control to control the speed and rotating power of the cutting assembly motor; Figure 16 is a diagrammatic and schematic illustration of one possible equivalent arrangement of the motor windings;

Figure 17 is a diagrammatic illustration of the air coolant system; and

Figure 18 is a diagrammatic illustration of a water coolant system which may be operably employed in accordance with the principles of the present invention in a tunneling machine incorporating the principles of the present invention.

As shown on the drawings:

There is illustrated in Figures 1 and 2 atunneling machine which embodies the principles of the present invention and which is indicated generally at 10. This tunneling machine 10 is operable to bore a clean cylindrical tunnel at much greater speeds than was heretofore possible by the conventionally used techniques of blasting and rock shattering and the like. In the cutting process the tunneling machine 10 preferably cuts a cylindrical shell type recess 11 into the rock 12 leaving a core 13 in the debris canister or shell 14 which core 13 may then be removed as a solid usable rock column or which may be crushed or shattered or broken away and otherwise removed as desired. The removing means forms no part of the present invention and may be of any well known form, so'need not herein be shown or described in detail.

The shell recess 11 which is cut in the earth or rock or the like 12 is cut by a rotatable cutting ring assembly 16 which is mounted at the front end 17 of the debris canister 14 for rotation about its axis and about the axis of the debris canister 14 since the ring assembly 16 is coaxially mounted with the debris canister 14. The cutting ring assembly 16 is arranged to rotate peripherally about the front end 17 of the debris canister 14.

The debris canister 14 is preferably cantilever mounted by a bracket and structural member arrangement 18 on the front end of the driving and control unit 15 so that the canister 14 is fixedly secured to the driving control unit 15 for forward and rearward movement in the tunnel without rotation of the canister 14.

The driving and control unit 15 has a rigid structural frame 19 for housing the operator controls and the like and the forward and rearward drive mechanism 20 (Figure' 6). The operator controls and the like may be mounted in panel boards 21 (Figure 6) and the like along a'wall of the driving and control unit frame 19 and the controls therein may be such controls as air system controls and water system controls and electrical controls for the various electrical units employed in conjunction with this invention.

The drive mechanism 20 is operatively coupled to a plurality of rolling trucks 22 which are secured to the underside of the frame 19 and which rollingly support the entire tunneling machine on tracks 23 shown in details in Figures 8 and 9.

The tracks 23 are preferably anchored directly to the floor or wall face of the cylindrical or circularly crosssectioned tunnel, and since the tunnel has the described configuration as cut by this tunneling machine, the tracks are adapted to be positioned and secured in interfacial engagement with the wall or floor face of the tunnel.

To this end, the tracks 23 are preferably constructed from a plurality of longitudinally arranged rail sections 2424 which have a cross-sectional configuration as illustrated in Figure 9. This cross-sectional configuration is substantially right trapezoidal so that the angularly disposed bottom face 25 thereof Will lie in interfacial engagement with the floor or face of the tunnel.

That is, by forming the rails 24 with a substantially trapezoidal cross-sectional configuration or a substantially right trapezoidal cross-sectional configuration, the rail will be provided with a pair of slides 2626 which may have any desired configuration but for purposes of convenience are described as straight or parallel sides, an

images the diameter of the curve of the tunnel. With this configuration for the rails 24, they may be disposed with the bottom faces 25 thereof in interfacial engagement with the side of the tunnel so that straight parallel sides 26-26 are vertical to properly support the trucks 22 bearing on the rolling Surface 27 of the rails 24.

I To couple the rails 24-24 together and to securely hold them in position and anchored to the face of the tunnel, as the tunneling machine moves along, the ends of the rails 24-24 are provided with axially or longitudinally extending locking pin receiving apertures 28 which receive a pin 29 slidably held ,near the tunnel wall by a rail mounting stud 30 and more particularly in a pin receiving aperture 31 in the head 32 of the stud.

The stud 30 is anchored in the tunnel by threading the same into an expanding sleeve 33 which is set in a drilled recess 34 in the tunnel wall. The head 32 of the stud 30 preferably has a height less than the full height of the rails 24 and is substantially triangularly shaped with forward and rearward sloping faces 35-35 which will conform to sloping faces 36-36 cut in the ends of the rails 24. The rails also have vertical abutting end faces 37-37 so that when the rails are locked in place by receiving the pins 29 in the recesses 28 and anchoring the studs in recesses 34, the rails will provide continuous tracks for the trucks of the tunneling machine. In an exemplary embodiment of this invention wherein the tunneling machine is adapted to bore a tunnel of, for example, about six feet in diameter, the rails 24 will preferably be constructed in about five foot lengths so that they may be laid ahead of the driving control unit 15 through access space in the region of the mounting bracket and structural arrangement 18.

The rails 24-24 are again seen in cross-section in Figure 6 which shows the manner in which the rails bearingly support the trucks 22 on which the driving and control unit 15 is carried.

The trucks 22, being shown as about eight in number in Figure 2, each including the cross bracket 38 (Figure 6) which is secured to the frame 19 along the underside thereof and more particularly to the longitudinally extending rails 39 (Figure 4) along the underside of the frame. The ends of the truck brackets extend upwardly for a short distance along the sides of the frame 19 as indicated at 4it-4tl for better securing of the trucks to the frame 19. Depending from each of the brackets 38 are bearing bars 41-41 and 42-42 at each end thereof. Thus there is a pair of depending bearing bars at each end of the brackets 38 and these bearing bars 41-41 and 42-42 are apertured and/or equipped with bearings for journaling a transversely extending shaft 43. This shaft 43 has a pair of wheels 44-44 secured thereto in the region of each end thereof for rotation therewith. The wheels 44-44 are positioned so that one thereof lies between the journal bearing brackets 41-41 and so that the other thereof lies between the journal bearing brackets 42-42. v

The wheels 44-44 will rollingly engage the tracks 23 and are so configurated as to substantially positively receive the upper surface 27 (Figure 9) of the rails 24. This is done by peripherally recessing each of the wheels 44-44 with arcuate peripheral recesses 45. Also, so that the wheels may be disposed to roll as close to the floor or cylindrical wall of the tunnel as possible, the outer rim 46 of each of the wheels has a lesser di \ameter than the inner rim 47 of each thereof. This arrangement not only allows for the maximum and most efiicient use of space in the tunnel but also provides for stability of the tunneling machine since any tendency for the machine to twist or rotate will be overcome not only by the action of the wheels riding on the rails but also by the tendency for the wheels to ride towards the center and bottom of the tunnel whereby the wheels will have a tendency to maintain a tunneling machine in the desired, erect and leveled position.

To drive the wheels 44-44 and thereby drivethe tunneling machine controllably forwardly or rearwardly as desired, there is provided a controllable drive mechanism which is indicated generally at 20 and includes .motor means 48 which may be an electric motor or some other form of motorsuch as an internal combustion engine or the like and which has an output shaft 49 connected to a gear box 50 or the like which together with the motor 48 is mounted on a floor plate 51 in thecontrol and drive unit '15 and more specifically on the frame 19 thereof. The output shaft 52 of the gear box. 50 rotatably carries a gear 53 or sprocket or the like which drives a chain 54 that drivingly couples the gear 53 to a gear 55 on one of the shafts 43 of one of the trucks 22. The gear or sprocket or the like 55 on the shaft 43 is keyed or otherwisesecured thereto for rotationtherewith so that'energization of the motor or engine 48 will operate to rotate the shaft 43 of said one of the trucks.

In addition, each of the shafts 43 carries a pair of gears or pulleys 56-56 and 57-57 at each end thereof and so orientated that the pulleys or gears 57 of 'the several trucks may be coupled together as by belts or chains 58 and so that the pulleys or gears or sprockets 56 may be coupled together as by beltsor chains 59. In this way driving of the gear 55 will be operative to rotate all of the shafts 43 and thereby drive all of th wheels 45. V The frame 19 of the drive and controlunit =15 is illustrated in section in Figures 4, 5 and 6 where it is shown to have a plunality of'longitudinal channels 39-39- 39-39 which extend longitudinally of the frame 19 at the four corners thereof. Vertical channels, or posts; 60 space the several channels 39 at each side of the drive and control unit and are secured thereto as. by welding or the like. Also, transversely extending channels 61 are secured to the longitudinal channels 39 and spacev the same horizontally at the top and bottom of the drive and control unit frame 19. These several structural members 39, 60 and. 61 provide great strength to the frame '19 and are able to support the entire tunneling machine. In addition such means as floor and .roof plates 51-51 are secured tothe horizontal structural members 61 to add strength to the frame and further to provide a floor and protection roof to the main housing control unit so that the mechanisms and instruments and controls therein and so that operators therein may safely ride in the driving control unit. At the front-end thereof, the floor and'roof plates 51 are bent or flanged inwardly as at 62 or provided with inward and transversely extending flange plates 62 which are secured to the floor and roof plates '51 to provide the first element of the bracket and structural assembly 18 which cantilever supports the debris canister 19. Side flange posts or plates 63 (Figure 4) are secured to the front end structural posts also to form a part of the bracket arrange ment 18. Studs or bolts 64-64 extend through the roof and floor plates 51 in double pairs to anchor upper and lower anglebrackets 65-65 to the front end of the frame 19. These angle brackets 65-65 include stress plates 66-66 which are perpendicular to the planes of the right angle brackets 65-65 and which properly support the legs 65a and 65b of the brackets 65. Similar brackets 67 having legs 67a and 67b with stress plates 68 are secured to the sides of the frame 19 as by bolts or studs 69 or the like extending through the vertical frame posts 60 or plates 70 mounted thereon. These several brackets 65 and 67 are disposed about the front end of the frame 19 at right angles with respect to each other and extend radially outwardly therefrom. The brackets '65 are shown in Figure 4 as extending vertically and as being aligned with respect to each other, while the brackets ;67 are shown as extending horizontally and are in alignment with each other and have secured thereto a pair of spaced circular plates 71 and 72 by means of studs or bolts 73 wearing collars 74 to properly axially space the circular plates 71 and 72.

. Also, a set of channels 75 are disposed between the plates 71 and 72 and surround 21 preferably substantially rectangular access aperture 76 in the plates 71'and 72 which permit entry into the canister 14 from the drive and control unit 19. An additional set of structural channels 77-77 lie between the rearward plate 71 and the flange plates 62 and 63 and are secured in position by bolts or the like 78 which extend through the flange plates 62 and 63, through the channels 77, through the rearward plate 71 and through the structural channels 75 and the forward plate 72to secure all of those members securely together and to peripherally seal the access passage between the driving control unit 19 and the canister 14.

' In Figure 4 the access apertures 79-79 in the forward end of the floor plate 51 will be seen. These access apertures 79 in the floor plate permit exit from the forward end of the drive and control unit 19 to set and secure and lay the tracks 23 ahead of the forwardmost truck under the frame 19.

The hereinabove described bracket and structural support 18 is operative to cantilever support and mount the canister 14 by securing the pair of substantially coextensive and coaxial drums 80 and 81 to the plates 71 and 72. That is, the outer drum 81 has the inner surface of the rearward end thereof peripherally secured to the plates 71 and '72 as by welding or the like at '82 and 83 respectively. These drums, the inner drum 80 and the outer drum 81, are spaced apart by a great plurality of studs '84 (shown in great detail in Figure 11) so that the inner drum 80 is supported on the outer drum 81. Also the rearward end 85 of the inner drum 81 may be secured to the forward face of the forward support plate 72 as by welding or the like at 86. Before considering a further detail of the canister construction, it should be noted that the inner drum 80 is provided with a plurality of spaced access apertures -87-87 therein which permit the operator access to ducts between the canister drums for the support and passage of coolant lines such as water lines and airlines and electrical conductors and electrical conductor conduits longitudinally of the canister 14 to the cutting assembly 16 which is mounted at the forward end of the canister 14. Coolants such as water and air and the like are stored on the tunneling machine for passage through the respective pipes and tubes therefor to the cutting assembly 16 by segmentally cylindrical tanks "88 (note Figure 3) which store such coolant fluids. 'Ihese tanks are, as stated, preferably segmentally cylindrical and have an outer cylindrical shell wall 89 which has a diameter slightly less than the diameter of the tunnel. The inner walls 90 of the tank are preferably disposed in a substantially rectangular configuration which will fit onto the frame 19 to be carried by the drive and control unit. Various apertures and connections 91 and the like permit connection of the proper tubes and hoses etc., to the tanks for the supply of fluid to the cutting assembly 16 and funnels 92 or the like permit convenient filling of at least the water tanks 88. The air tanks 88 will be filled by other convenient means.

In Figure 11 it will be seen that the innerdrum 80 and the outer drum 81 are provided with a great plurality of aligned radial apertures 93 and 94 respectively for receiving pins or studs 84 or the like. As shown in Figure 11, these pins or studs 84 are provided with a pair of shoulders 9595 near opposite ends thereof spaced from the ends of the pins by a distance substantially equal to the thickness of the drums 80 and 81. The shoulders 9S-95 on each of the pins 84- 84 thus properly radially space the two substantially co-extensive coaxial drums '80 and 81. The end portions 96 of the pins permit securing of the pins to the drums as by riveting or welding or the like. a Ducts between angularly adjacent pins 84 provide space for water pipes 97 which supply water from the water tanks 88 of Figures 1, 3 and 18, to a plurality of water or other cutting fluid and coolant nozzles 98' which ex-' tend through appropriate apertures 99 in the inner canister drum 80. The coolant passage 97 may actually be a pipe connected to the output of a pump 100 schematically indicated in Figure 18 but located in the drive and control unit 15. In addition such means as valves 101 may be provided at the inlet and outlet of the pump 100 and a meter 102 may be used to indicate the liquid pressure at the outlet of the nozzles 98.

Electrical conductors 103 may also pass through the duets with the pipes 97 for connection to the electric motor windings 104 on the magnetic pole pieces 105 which form a part of the cutter assembly (16.

The cutter assembly 16 has a cutter ring 106 which is mounted on the front end of the canister 14 for floating and rolling rotation peripherally thereabout and coaxially therewith. This cutter ring 16 has an annular recess 107 in the rearward end thereof which recess 107 has a radial dimension slightly greater than the radial dimension across the drums 80 and 81 so that the drums 80 and 81 may fit into the recess 107. By providing a few threads 108 and 109 on the inner face of the inner drum '80 and on the outer face of the outer drum 8-1 at the extreme forward end thereof and a few threads 1 10 and 111 on the inner faces of the recess 107 to mate with the threads 198 and 109 respectively, the ring 106 may be screwed onto the canister 14. The threads 103, 109, and 111, have a sufliciently short axial dimension so that when the ring 106 is fully mounted on the canister 14 the several threads will be out of engagement with each other and the ring .106 may then be free floating for coaxial rotation on the canister 14. To further rotatably support the cutting ring 106 on the canister 14, such means as ball bearings 112 112 may be provided on the inner side of the drum 80 and the outer side of the drum 31 to engage threads 110 and 111 respectively and to roll between the threads and the drums, and ball bearings -1131 13 may be provided in annular recesses 114-114 in the bottom face of the groove 107 to roll against the end edges of the plates 80 and 81.

In addition, small annular abutment shoulders 1Cl5 115 are provided on the inner face of the drum 80 and the outer face of the drum 81 to limit rearward movement of the ring 196 on the canister 14 and further to cooperate with the ball bearings 113113 to provide thrust to the cutting ring 106 when the machine is driven forwardly.

The cutting ring 166 is tapered forwardly radially outwardly on both its outer annular surface 116 and its front face 117 so that the shell cylindrical recess cut in the rock by the cutting action of the ring .1 16 will be sufliciently greater in dimensions to permit the canister 14 to pass thereinto without binding on the faces of the rock. The actual cutting, however, is done by a plumb ity of cutting teeth, for example about 20 cutting teeth, which are removably dovetail secured to the front face 117 of a cutting ring 106 as indicated generally at 118. That is, the front face 117 of the cutting ring 106 has a plurality of sets of dovetail like grooves and lands therein while the cutting teeth blocks 119-1119 are correspondingly provided with dovetail type lands and grooves in he rearward face 129 thereof so that the cutting teeth blocks 119 may be removably secured to the front face 117 of the cutting ring 106.

The cutting teeth 119 are constructed in accordance with the principles of the present invention by blocks of abrasive material or by blocks of other rigid material alternating current.

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9 carrying a particulate abrasive coating on the front face thereof or having abrasive particles such as the diamonds 121 secured and imbedded in the front face thereof for smoothly, carefully and efficiently cutting away the rock as the ring 106 of the cutting assembly 16 is rotated and as the tunneling machine is driven forwardly.

To rotate the cutting ring 106 of the cutting assembly 16 there is provided a motor of which the pole pieces 105 form a part and which is cooled by air fed through the ducts and between the inner and outer drums 80 and 81 from air tanks 88 as illustrated in Figure 17. In Figure 17 it is shown that air may be supplied to the shell space between the inner and outer drums 80 and 81 from the air tank 38 through an air conduit 122. A- meter 123 or the like in the air line 122 and positioned within the control and drive unit 15 may be employed to register the pressure of the air flowing through the canister 14. The air may be supplied to the tank 88 from any desired outside source or be continuously pumped thereinto as by pump 124 having an outlet 125 feeding into the tank 88.

With particular reference to Figures 11 and 12 the construction of the cutting ring assembly drive motor may be most easily understood. This motor is preferably one of the induction alternating current type which is operable to be driven preferably by a three phase source of The motor itself is constructed by securing a stator 126 to the inner face of the outer drum 81 within the recess 107 of the rotating cutting ring 106, and securing a rotor 127 to the inner wall of the recess 107 of the ring 116. The rotor 127 extends inwardly of the inner wall of the recess 107 in spaced relation with respect to the stator 126 in the outer face of the inner'drum 80 andis coaxial with the stator 1 26 and substantially coextensive therewith.

The stator 126 actually includes only the plurality of motor pole pieces 105 each of which carries a winding or coil 104. The rotor, on the other hand, has a conductor ring of highly conductive material such as aluminum or copper or the like and indicated at 128 which has its forward peripheral edge secured to the bottom face of the recess 107 by such means as screws 129 extending through the ring 106 from the front face thereof and counter-sunk thereinto. Magnetic pole elements 130 which preferably consist of a plurality of laminations secured together are recessed into the outer face of the conductor ring 128 so that the outer face thereof is flush and smooth and may lie in close proximity to the radially inner face of each of the pole pieces 105.

Each of the pole pieces 105 has an inner and an outer pole plate 131 and 132 formed of a plurality of laminations of magnetic material and secured together. A magnetic core member 133 also of magnetic laminated construction spaces the pole plates 131 and 132 so that the winding 104 may be disposed about the core piece 133 and between the pole plates or pole shoes 131 and 132. This assembly, with the pole shoes and the pole core secured together, is secured to the inner face of the outer drum 81 by such means as screws 134 or the like which extend through the outer drum 81 and into the poles 105.

It should further be noted that the poles 105 are so constructed that at least the radially inner face of the inner pole shoes 131 substantially form an annulus which has a minimum clearance to the rotor conductor ring 128 and the magnetic inserts 130 therein yet permitting rotation of the rotor ring.

When the pole pieces and the windings 104 thereon are energized the poles will be in magnetic circuit relation with the magnetic inserts in the rotor ring so that an electric motor of the induction type will be so energized that the rotor will cause rotation of the cutting assembly 16 in the desired manner coaxially with the canister 14. Another important feature of this electric motor embodying the principles of the present invention is that by virtue of its construction and operating principles the cutting 10 ring 106 will substantiallymagnetically float in its rota tion on the canister 14 and thereby be substantially frictionless in its rotation thereabout.

A motor embodying the principles of the present invention and one which is suitable for use with and in a tunneling machine to bore a tunnel of, for example, about six' feet in diameter, is schematically illustrated in Figures 13 and 14 wherein the three phase induction motor is illus trated as one having about sixty poles, or twenty poles for each phase. The poles are shown as grouped. together and aligned for the A, B and C phases. Each of the windings is identified as A1 A20, B1 B20 and C1 C20.

By utilizing sixty poles and windings, the motor may be variously connected to have various output speeds andpowers as desired. For efiicient operation, however, in this size unit, it is desired to connect each or" the several windings together in groups of five such as A1 through A5, A6 through A10, All through A15, A16 through A20, B1 through B5, and C1 through C5, and C16 through C20. In each group such as the group of A1, A2, A3, A4 and AS, the windings are connected together in series for simultaneous energization. The terminals of each series group such as terminals Aa and Ab for the group of windings A1 through A5, are brought out and led back to the drive and control unit where control means are provided for variously connecting and reconnecting the windings and the terminals to a source of three phase energy so that various speeds and powers etc.,may be obtained for driving the cutter assembly. This series connection of the windings together in groups of five permits efiicient control of various power inputs to the motor, particularly when the windings are physically arranged in the motor as indicated schematically in Figure 14 wherein it is shown that the windings are physically placed in an order such as A1, B1, C1, A2, B2, C2, A20, B20, and C20.

Here it .will be noted that the magnetic elements of the rotor are substantially greater in number than the number of wound poles on the stator and when the number of wound poles on the stator are sixty, the number of magnetic elements and inserts 130 in the rotor 127 may be about seventy or about seventy-two. In the arrangement of Figures 13 and 14 power is provided to the windings by energizing them in accordance with A, B and C phases of the input power supply so that the windings A1 through A5 are energized to their maximum immediately before the windings B1 through B5 which are in turn energized to their maximum immediately before the windings C1 through C5 etc., so that the rotor magnetic elements will be attracted to rotate the rotor and thereby rotate the cutter assembly '1 6. Since the windings A1 through A5 etc., are connected together in series in groups of five, however, there is illustrated in Figure 6 an equivalent circuit arrangement showing twelve poles which are equivalent of the twelve groups A1 through A5, A6 through A10 etcL, C16 through C20 having terminals Aa-Ab, etc., to Cg-Ch. A controller for controlling the power to these windings is shown in equivalent form in Figure 15 wherein equivalent terminals Aa through Ch are shown for each of the terminals of the groups of windings and wherein there is further shown connector bars such as drum control type connector bars for connection of these terminals to a source of power.

In Figure 15 the three phase source of power leads are identified as leads X, Y and Z respectively which are connected to certain of the hereinbelow identified controller bars. Certain other of the controller bars are connected to other central leads for a Y three phase connection of the windings through controllable rheostats 135135135 to a central connection 136.

In the first position of the controller the several windings will be so connected that the contact Aa will be connected to the conductor bar 137 and therethrough to the power lead of the X or A phase. The other connections will be such that power will flow through all of the windings A1 through A20 in series since the terminal Ab will be connected to the contact bar 138 which in turn will connect the same to the terminal Ac of the windings A6 through A10 having a terminal Ad connected to the contact bar 139 which in turn is connected to the terminal Ae of the windings All through A15. The other terminal A of the windings All through A15 will be in contact with the contact bar 140 which in turn is connected to the terminal Ag of the windings A16 through A20 having the other terminal Ah thereof connected to the contact bar 141 which will lead through a lead 142 to the rheostat 135 and thence to the neutral point 136. The B or Y and the C or Z phases will, in turn, also be entirely connected in series respectively leading through leads 143 and 144 to the rheostats 135 and therethrough to the terminal point or neutral point 136.

In the second stage of the controller unit, the windings A1 through A5 will be in series with the windings A6 through A10 and in parallel with the series connected windings All through A20. Thus the terminals Ab and Ac will again be connected together as will the terminals A and Ag but the terminals Aa and Ae will be connected to the X phase lead respectively through the bars 137 and 145. The terminals Ad and Ah will be connected to the neutral point through connector bars 146 and 141 respectively. In this second stage the Y and Z phases will be similarly connected with the windings B1 through B10 being connected in series with each other and in parallel with the windings B11 through B20 which are connected in series and the windings C1 through C10 being connected together in series and in parallel with the windings C11 through C20.

In the third stage of operation of the controller all of the groups of each phase respectively will be connected in' parallel so that the windings A1 through A5 will be in parallel with the windings A6 through A10 and in parallel with the windings All through A15 and also in parallel with the windings A16 through A20. This is accomplished by connecting the A or X phase lead to the bars 137, 145, 147 and 148 which are respectively connected to the terminals Aa, Ae, Ad, Ah. At the same time the terminals Ab, Ac, Ag and A will respectively be connected to the controller contact bars 149, 150, 151

and 152 which lead to the neutral point 136 through a variable resistance 135.

The B and C or Y and Z phases are similarly so connected that the several windings of each phase group will be connected in parallel with each other.

Thus it will be observed that with this exemplary form of controller embodying the principles of the present invention for this new and improved motor, several variations of power and speed may be obtained. It will be observed, of course, that numerous variations in the manner of connection in the types of controllers which may be employed can be effected without departing from the true spirit and scope of the novel concepts and principles of this invention to effect the desired speed and power changes. It will also be observed that numerous other variations and modifications may be made in the several phases and parts of machines embodying the principles of this invention without departing from the spirit and scope of the principles of this invention. 1, therefore, intend to cover all such modifications and variations as fall within the true spirit and scope of the novel concepts and principles of my invention.

I claim as my invention:

1. In a tunneling machine to bore a tunnel through earth and rock and the like and having supporting and propelling mechanism including a cylindrical drum, a cutting ring having forwardly disposed cutting teeth thereon rotatably supported on said drum and extending forwardly therefrom, and an electric motor having a rotor element and a stator element, said rotor element being secured to and forming a part of said cutting ring and said stator element being fixedly mounted on said drum.

2. In a tunneling machine to bore a tunnel through earth and rock and the like and having supporting and propelling mechanism including a cylindrical drum having inner and outer walls, a cutting ring having forwardly disposed cutting teeth thereon rotatably supported on the inner and outer walls of said drum and projecting forwardly therefrom, and an electric motor having a rotor element and a wound stator element, said rotor element being secured to and forming a part of said cutting ring and said wound stator element being fixedly mounted on said drum within the margins of said cutting ring in juxtaposition to said rotor element, whereby energization of said stator element will cause rotation of said rotor element and said cutting ring about its axis.

3. In a tunneling machine to bore a tunnel through earth and rock and the like and having supporting and propelling mechanism including a cylindrical drum having inner and outer walls, a cutting ring having forwardly disposed cutting teeth thereon, rotatably supported on the inner and outer walls of said drum and extending for wardly therefrom, and an electric motor having a rotor element and a stator element, said rotor element comprising a ring of good electrically conductive material secured to said cutting ring and a plurality of magnetic elements secured to said conductive ring, and said stator element comprising a plurality of magnetic elements mounted on said drum within the limits of said cutting rings in juxtaposition to said rotor element, and a winding carried by said magnetic elements of said stator whereby energization of said stator element will cause rotation of said rotor element and said cutting ring about its axis.

4. In a tunneling machine to bore a tunnel through earth and rock and the like and having supporting and propelling mechanism including a cylindrical drum having inner and outer walls, a cutting ring having forwardly disposed cutting teeth thereon rotatably supported on the inner and outer walls of said drum, and an electric motor having a rotor element and a stator element, said rotor element comprising a ring of good electrically conductive material secured to said cutting ring and extending parallel to the walls of said drum and a plurality of magnetic elements set into recesses in said conductive ring, and said stator element comprising a plurality of magnetic elements mounted on said drum within the limits of said cutting ring in juxtaposition to said rotor element, and a winding carried by said magnetic elements of said stator whereby energization of said stator element will cause rotation of said rotor element and said cutting ring about its axis.

5. In a tunneling machine to bore a tunnel through earth and rock and the like, a cylindrical debris canister, a control and driving unit secured to and supporting said canister in forwardly extended relation with respect thereto, and a rotary cutting assembly mounted on the front end of said canister and extending about the inner and outer periphery thereof, said rotary cutter assembly comprising a cutting ring having forwardly disposed cutting teeth thereon and rotatably supported on said canister, an electric motor stator including a plurality of magnetic pole pieces secured to said canister and a winding on each of said pole pieces, and a motor rotor including a ring of good electrically conductive material secured to said cutting ring in juxtaposition to said pole pieces and a plurality of magnetic elements secured to said conductive ring and in magnetic circuit relation with the magnetic pole pieces.

6. In a tunneling machine to bore a tunnel through earth and rock and the like, a control and driving unit, a debris canister secured to said unit forwardly thereof and having a pair of coaxial coextensive cylindrical drums, and a rotary cutter assembly rotatably mounted on said drums and extending forwardly thereof and peripherally about the inner and outer of said drums, said rotary cutter assembly comprising a cutting ring having forwardly disposed cutting teeth thereon and rotatably supported on said canister externally of the outer drum and internally of the inner drum, an electric motor stator including a plurality of magnetic pole pieces secured to the inner face of the outer drum, and a winding on each of said pole pieces, and a motor rotor including a ring of good electrically conductive material secured to said cutting ring and extending between said drums and disposed between said pole pieces and the exterior of the inner drum and a plurality of magnetic elements secured to said conductive ring and in magnetic circuit relation with the magnetic pole pieces.

7. In a tunneling machine to bore a tunnel through earth and rock and the like, a control and driving unit, a debris canister secured to said unit forwardly thereof and having a pair of coaxial coextensive cylindrical drums and a rotary cutter assembly mounted on said canister forwardly thereof and peripherally thereabout, said rotary cutter assembly comprising a cutting ring having forwardly disposed cutting teeth thereon and rotatively supported on said canister externally of the outer drum and internally of the inner drum, an electric motor stator including a plurality of magnetic pole pieces secured to the inner face of the outer drum, and a winding on each of said pole pieces, and a motor rotor including a ring of good electrically conductive material secured to said cutting ring and disposed between said pole pieces and the exterior of the inner drum and a plurality of magnetic elements secured to said conductive ring and in magnetic circuit relation with the magnetic pole pieces, the number of said magnetic elements being greater than the number of said pole pieces.

8. A tunneling machine for cutting a tunnel in earth and rock and the like comprising a mobile frame forming a drive and control unit operable to drive the tunneling machine forwardly and rearwardly, a generally cylindrical canister supported on said frame and extending in advance thereof, an annular rotary cutter assembly rotatably mounted on the forward end of said canister for rotation thereabout, said cutter having an annular forwardly extending cutting face inclined outwardly from the inner margin thereof and extending radially beyond the periphery of said canister to cut clearance therefor, and motor means mounted on said canister and said cutter assembly for driving said cutter assembly about the forward end of said canister to make an annular cut in the tunnel face.

9. In a tunneling machine, a drive and control mechanism therefor including a mobile frame, a generally cylindrical canister extending in advance of said frame, a cantilever support mounting said canister on the forward end of said frame to extend in advance thereof, an annular rotary cutter assembly mounted for rotation about the forward end of said canister, said canister comprising a pair of coaxial substantially coextensive cylindrical drums and a plurality of spacing studs disposed therebetween supporting said drums in fixed relation with respect to each other, means for rotatably mounting said cutter on the inner and the outer of said drums to rotate thereabout and motor means mounted on said drums and said cutter assembly for driving said cutter assembly to make an annular cut in a tunnel face.

10. In a tunneling machine adapted to bore tunnels through earth, rock and the like, a drive and control mechanism, a generally cylindrical debris canister at the front of said drive and control mechanism, a cantilever support mounting said canister on said drive and control mechanism to project forwardly therefrom, a rotary cutter assembly mounted for rotation at the front end of said canister and peripherally thereabout, said canister comprising a pair of coaxial substantially coextensive drums and a plurality of spacing stud-s secured to said drums and disposed therebetween to support and space the same, and means defining a duct between said drums for coolant conduits and electrical conductors to extend from said mechanism to said cutter assembly, means journalling said cutter assembly on the inner and outer of said drums for rotation thereabout, and motor means connected with said electrical conductors having one part on one of said drums and another part on said cutter assembly, for rotatably driving said cutter assembly upon energization of said motor means.

11. In a tunneling machine for boring tunnels through earth, rock and the like, a drive and control mechanism including a mobile frame, a generally cylindrical debris canister mounted on said frame and extending in advance thereof, a rotary cutter assembly at the front of said canister, said canister comprising a pair of spaced apart coaxial substantially coextensive drums, the space between said drums defining a duct for cooling conduits and the like, means rotatably mounting said cutter assembly on the forward ends of said drums to project forwardly therefrom, motor means on said drums and said cutter assembly for rotatably driving said cutter assembly to make an annular cut in a tunnel face, segmental generally cylindrical coolant tanks supported on said frame and forming a rearward continuation of said canister, and means for conducting coolant along the space between said drums to said rotary cutter assembly.

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